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**Tamlin** · 07-18-2006

OK, let's try a different approach.

When you load an image in Photoshop, it is composed of a number of "channels". How many depends on the image mode: RGB images are composed of 4 channels - Red, Green, Blue and a composite of all 3. CMYK images have 5 channels: Cyan, Magenta, Yellow and Black, plus a composite. Indexed colour, Duotone and Grayscale have just one. Each channel holds information about a particular colour element in the image. You can think of individual channels as being like plates in the printing process, with a separate plate supplying each layer of colour.

But it doesn't stop there. The Channels palette can also contain alpha channels, which have a number of uses. One of the most common uses is to store selections or paths so you can use them later.

Channels can be edited individually so you can blend certain ones, or alter the colour of just one channel. You can also achieve interesting results by applying filters to just one channel.

So to sum it up, channels are a useful tool when it comes to colour management or using (and reusing) selections. If you look at some of the tutorials that deal with these subjects, you'll probably find examples of channels in use, which may help you to understand what you can do with them.

I just did a quick search and found these...

This 4-page article was written about channels in Photoshop 6, but most, if not all, of the information still holds true for all versions up to and including CS2:

http://www.arraich.com/ps6_tips_channels1.htm

This article covers channels in both Photoshop and Paint Shop Pro:

http://www.webreference.com/graphics...n41/index.html

Here's a tutorial that shows you how to create a transparent image, using an alpha channel:

http://www.axialis.com/tutorials/tutorial-misc001.html

This tutorial shows you how to mask difficult subjects using channels:

http://www.photoshopcafe.com/tutoria...ng/masking.htm

This tutorial covers colouring line-art using channels:

http://www.tutorialized.com/tutorial...a-Channels/505

Well, that's a few to be going on with...

07-18-2006	#8 (permalink)
Tamlin Janitor of Lunacy Join Date: May 2006 Location: Sitting in the Wishing Chair Posts: 5,425	OK, let's try a different approach. When you load an image in Photoshop, it is composed of a number of "channels". How many depends on the image mode: RGB images are composed of 4 channels - Red, Green, Blue and a composite of all 3. CMYK images have 5 channels: Cyan, Magenta, Yellow and Black, plus a composite. Indexed colour, Duotone and Grayscale have just one. Each channel holds information about a particular colour element in the image. You can think of individual channels as being like plates in the printing process, with a separate plate supplying each layer of colour. But it doesn't stop there. The Channels palette can also contain alpha channels, which have a number of uses. One of the most common uses is to store selections or paths so you can use them later. Channels can be edited individually so you can blend certain ones, or alter the colour of just one channel. You can also achieve interesting results by applying filters to just one channel. So to sum it up, channels are a useful tool when it comes to colour management or using (and reusing) selections. If you look at some of the tutorials that deal with these subjects, you'll probably find examples of channels in use, which may help you to understand what you can do with them. I just did a quick search and found these... This 4-page article was written about channels in Photoshop 6, but most, if not all, of the information still holds true for all versions up to and including CS2: http://www.arraich.com/ps6_tips_channels1.htm This article covers channels in both Photoshop and Paint Shop Pro: http://www.webreference.com/graphics...n41/index.html Here's a tutorial that shows you how to create a transparent image, using an alpha channel: http://www.axialis.com/tutorials/tutorial-misc001.html This tutorial shows you how to mask difficult subjects using channels: http://www.photoshopcafe.com/tutoria...ng/masking.htm This tutorial covers colouring line-art using channels: http://www.tutorialized.com/tutorial...a-Channels/505 Well, that's a few to be going on with... __________________ "It's just the way the operation made me" Last edited by Tamlin; 07-18-2006 at 09:23 PM..